<h4>Tool</h4><table border="0"><tr><td valign="top"><b>Name</b></td><td valign="top">Downslope Distance Gradient</td></tr><tr><td valign="top"><b>ID</b></td><td valign="top">9</td></tr><tr><td valign="top"><b>Author</b></td><td valign="top">(c) 2006 by O.Conrad</td></tr><tr><td valign="top"><b>Specification</b></td><td valign="top">grid</td></tr></table><hr><h4>Description</h4>Calculation of a new topographic index to quantify downslope controls on local drainage. 

References:
- Hjerdt, K.N., McDonnell, J.J., Seibert, J. Rodhe, A. (2004):   'A new topographic index to quantify downslope controls on local drainage',   Water Resources Research, 40

<hr><h4>Parameters</h4><table border="1" width="100%" valign="top" cellpadding="5" rules="all"><tr><th>Name</th><th>Type</th><th>Identifier</th><th>Description</th><th>Constraints</th></tr>
<tr><th colspan="5">Input</th></tr><tr><td>Elevation </td><td>Grid (input)</td><td>DEM</td><td></td><td></td></tr><tr><th colspan="5">Output</th></tr><tr><td>Gradient</td><td>Grid (output)</td><td>GRADIENT</td><td></td><td></td></tr><tr><td>Gradient Difference (*)</td><td>Grid (optional output)</td><td>DIFFERENCE</td><td>Difference to local gradient.</td><td></td></tr><tr><th colspan="5">Options</th></tr><tr><td>Vertical Distance</td><td>Floating point</td><td>DISTANCE</td><td></td><td>Minimum: 0.000000
Default: 10.000000</td></tr><tr><td>Output</td><td>Choice</td><td>OUTPUT</td><td></td><td>Available Choices:
[0] distance
[1] gradient (tangens)
[2] gradient (degree)
Default: 2</td></tr></table>(*) <i>optional</i>